Pedal control for rheostats



Dec. 19, 1950 E. H. ALKlRE PEDAL CONTROL FOR RHEOSTATS Filed Dec. 5,1949 IIVYENTOR fLBER/V h. ALK/RE I 'II Attorney Patented Dec. 19, 1950UNITED STATES PATENT OFFICE PEDAL CONTROL FOR RHEOSTATS V Elbern H.Alkire, Easton, Pa. Application December 5, 1949, Serial No. 131,166 3Clai1ns. (Cl. 201-48),

This invention relates to pedal. controls and, more. particularly, to apedal control for musical instruments.

In the playing of stringed instruments with whicha steel is .used, thebod of the instrument is generally supported on the artists right kneeand, if the instrument utilizes an electric amplifier, the right footrests on a control pedal. Prior to this invention, control pedals werepivoted to a base and had an upper surface lying in a plane'normal tothe vertical. The fulcrum' was usually in the center of the pedal, andthe entire arrangement was based on the assumption that. the. artistsfoot would extend straight forward... The .difliculties which thisinvention intends. to .cure are these: When the artists foot rests flatona prior art pedal, rockingof the foot .so as to .pivot the pedal alsocaused the right knee to raise and lower, thereby deleteriously changingthe level of the instrument. The unnatural position of the foot and kneealso induced fatigue in the artists leg muscles so as to cause crampsor, where nervousness was a factor, set up an involuntary shaking of theentire leg. If the artist points his foot to the right in effort tocompensate for this, then his foot does not rest fiat against the pedal.Depression of the pedal then entails both a forward and sidewise tiltingof the foot about the ankle joints. The object now is to provide a pedalwith a tread surface slanting downwardly from left t right, and with afulcrum matching, in location lengthwise of the pedal,the ankle fulcrumabout which the foot pivots. Thus, it is intended to provide a pedalwhich enables the artist to sit with his knees apart, and with his rightfoot turned somewhat to the right, and to keep his foot fiat against thepedal tread during all operations of the pedal while still keeping hisright knee in a uniform, comfortable position.

These and other objects will be apparent from the followingspecification and drawings, in which:

Fig. l is a side elevation of the pedal in depressed position;

Fig. 2 is a vertical section taken lengthwise through the pedal when inraised position showing the interior mechanism;

Fig. 3 is a vertical section taken transversely through the pedal alongthe line 3-3 of Fig. 1 looking in the direction of the arrows; and,

Fig. 4 is a vertical section taken transversely through the pedal alongthe lines 4--4 of Fig. 1 looking in the direction of the arrows.

Referring now to the drawing in which like elements are denoted bsimilar reference numerals, the pedal control unit indicated generallyat 2 includes a base 4 preferably cast of aluminum alloy or othersuitable light but rugged material with right and left-hand side walls 6and 8 and rear and front walls iii and [2, all integrally joined in onepiece. Also included in the casting is a rheostat pocket 26 describedbelow. It will be noted further that the side walls of the base i havetop edges 14 steeply inclined upwardly from rear wall It forwardly forabout one-third of the length of the base, and thence gently inclinedupwardly and forwardly as shown at 6 for the remainder of the baselength. The juncture of these edges forms a false fulcrum about which apedal i8 rocks, while top edges It and i4 constitute stops for the pedalrespectively at its extreme up and down positions.

As shown best in Fig. 4 pedal l8, also cast preferably of aluminum, isformed with a pair of lugs 29a, 291) depending from the pedalunder-surface 2!. The pivotal connection of pedal is to base casting 2is accomplished by a pivot pin 22 passing through suitable openings inside walls 6 and 8 and lugs 20a and 20b, the holes being arranged sothat the under-surface 2| of the pedal rolls just above the juncture ofedges l4 and i6.

Before further discussion of the important form of pedal i8, it will beobserved that the immediate object of the mechanism is to operate arheostat (not shown) contained in the rheostat pocket 26 of base casting2. The shaft 28 of the rheostat projects outwardly through the pocketwall and carries a pinion 3B driven by a rack 32 pivoted between ears 34on the under-surface 2i of pedal 5. Rack 32 is pulled against pinion 39by a tension spring 36 stretched between the rack and a lug 38 on thepedal under-surface. Suitable input and output connections dd, 42 arewired to the rheostat so that when pedal is is raised towards theposition shown in Fig. 2, rack 32 rotates pinion 30 counter-clockwise toturn the rheostat towards its off position. Then as pedal 18 is rockedforwardly about pivot pin 22 towards the Fig. 1 position, the rheostatis turned clockwise so as to increase the volume or power of theelectrical instrument with which it is in circuit via connections 40,42.

In operation, pedal I8 is maintained at varous angular positions betweenthe extremes illustrated in Figs. 1 and 2, with the instep of theartists foot substantially over pivot pin 22 and with the sole of theshoe planted fiat against the working surface of tread M. The artistsknees are separated somewhat wider than the feet and, in this position,the right foot is angled off to the right, and the sole of the shoe isinclined downwardly from left to right. This is because the ankle mosteasily turns about an axis parallel to the axis about which the kneeswings.

Referring particularly to Fig. 3, the clash line 2| extending to theleft represents an extension of the line of the pedal under-surface 2 l,and dash line H denotes the horizontal, the angle therebetween of fourdegrees being the angle of sidewise inclination of pedal l8 and of theworking surface of tread 14. The inclination is obtained by formingright-hand lug 20a somewhat shorter than left-hand lug 2th, and uniformengagement of the edges of under-surface 2| of pedal with top edges Hi,IQ of base 4 result from the downwardly projecting left-hand edge 48 ofpedal i8 thickened, or deeper as compared with its right-hand edge 48.

The invention detailed above is not limited to the specific embodimentillustrated but is intended to cover all substitutions, modificationsand equivalents within the scope of the following claims.

I claim:

1'. In a control unit, an elongate base having a relatively high frontwall, a relatively low rear wall, and side walls therebetween, each ofsaid side walls having a back portion substantially one-third the lengththereof and a forward portio-n substantially two-thirds the lengththereof,

said back portion having a top edge inclined reletively steeply upwardlyand forwardly from. said rear wall to the intersection of said portions,said forward-portion having a top edge inclining relatively gently fromsaid intersection upwardly and forwardly to said front wall, a pivotextending substantially transversely of said base substantially at saidintersection, an elongate pedal, means mounting said pedal on said pivotat a location substantially one-third along the length of said pedalfrom rear to front whereby said pedal may be rocked about said pivotbetween two extreme positions, in the first of which position said pedalengages against the top edges of said forward portions and in" thesecond of which positions said pedal engages against the top edges ofsaid back portions a rheostat affixed in said inset base, said rheostathaving a rotatable shaft extending horizontally, a pinion on said shaft,and a rack pivoted beneath said pedal and drivingly engaging saidpinion.

2. The combination claimed in claimv 1, said pedal having an upperworking surface inclined traversely from one longitudinal side to theother.

3. In the combination claimed in claim 1, a spring engaged between saidrack and said pedal and arranged to maintain said rack against saidpivot.

ELBERN H. ALKIRE.

REFERENCES CITED The following references are of record in th file ofthis patent: V

UNITED STATES PATENTS Number Name Date 1,267,890 Corey Dec. 1'7, 19181,351,023 Cantemerle Aug. 31, 1920 1,919,968 Trabold July 25, 19331,949,826 Chason Mar. 6, 1934 2,379,774 Wyer July 3, 1945 2,460,494Eisenberg et al. Feb. 1, 1949

